If robots evolved to the point they could be used as sexual companions

I think we all know that there is a time when robots will evolve to the point that they will be able to look and act on a level that they could replace most human functionality. That will with a doubt in most reasonable people's minds lead to a particular sect of society no matter how large, to see these robots as objects that can be used to provide services to humans on every conceivable level. In the beginning this could mean day care or nanny services, helping in nursing homes, you get the point.
If one could make robots that seem to act and feel real, at what point would someone try to give it emotional responses that seemed to pantomime those of humans. I'm not saying they could ever love, but a person could certainly love them.
All ethical dilemmas aside, imagine the long-term benefits of these actions. It could put an end to all prostitution and human trafficking, if robot escorts became cheaper and easier to maintain than their human counter parts, plus with maintenance and clean-up it could also take away any risk of STDs which would have no chance of being able to survive on any synthetic skin.

Would congress pass laws forbidding the use of robots for any and all sexual use? Would the people that did these actions be shunned or mocked by the majority of society? Would their be robot advocates that would speak out in favor of robot rights?

Oddly enough, in all of Assimov's books, I don't think he ever tackled the idea of human/robot sexual encounters. I'm left only with shoddy examples like the movie AI.

uh... the robots couldn't really process pain or pleasure. i'm pretty sure we will be wiped out by super antibiotic-resistant bacteria before we develop the tech to make artificial nervous systems and pleasure receptors.

It could bring pleasure, I'm sure, but not lasting satisfaction. I can pleasure myself with masturbation, for example, but what I deeply long for is the acceptance, touch, interest, attention, and devotion of another man. It would have to be a pretty damn sophisticated robot to pull that off.

I can see in the long run that hotels might start adding "companions" for tourists and businessmen far from home. Although you'll probably never heard it discussed in any official news forum its well known that in countries like Japan women are brought in from Thailand, Vietnam and Korea to service the sexual needs of businessmen, especially if they're virgins. Similar practices exist all over the world, especially in Asia. It's naive to believe that western tourism traveling to these Asian countries are to blame for the phenomenon. I'm not condoning this behavior, and am actually a member of a human rights coalition that fights human trafficking.

I think the military would be another market to cater to.

Would people in monogamous relationships consider it cheating, or would it be like catching you partner masturbating?